1. Field of the Invention
The invention relates to electrical connectors for coaxial cable. More particularly the invention relates to a coaxial connector with an outer conductor outer diameter gripping electro-mechanical interconnection suitable for coaxial cables with an unprepared cable end.
2. Description of Related Art
A positive stop type coaxial connector, for example as disclosed in commonly owned U.S. Utility Pat. No. 6,793,529 titled: “Coaxial Connector with Positive Stop Clamping Nut Attachment”, by Larry Buenz, issued Sep. 21, 2004, hereby incorporated by reference in its entirety, has a connector body and a back nut configured for threaded interconnection. As the connector body and back nut are threaded together, a flared leading edge of the outer conductor of the coaxial cable is clamped between the connector body and the coupling body in a secure electro-mechanical interconnection. To indicate proper threading completion and avoid damage to the connector and/or coaxial cable from over-tightening, a positive stop between the connector body and the back body may be applied wherein the threading between the back body and connector body bottoms at a specific axial location at which the desired maximum tightening compression/torque force occurs, definitively signaling the installer that the proper amount of tightening has been reached. To allow for thermal expansion cycling and/or variances in manufacture of the connector and/or the outer conductor dimensions, a compression element is inserted between internal contacting surfaces of the outer conductor, back body and/or the connector body. The compression element is typically supplied loose with the coaxial connector prior to installation, which creates a loss and/or damage risk for the compression element.
Prior positive stop type coaxial connector designs typically require flaring of the outer conductor to facilitate a clamp electro-mechanical interconnection between the connector body, the leading edge of the outer conductor and the back nut. Prior to installation, a coaxial cable must be specially prepared for a clamp type interconnection, to remove dielectric material and/or adhesive from the inner diameter of the outer conductor. Such cable end preparations typically require each installer to have on hand a specialized cable dielectric coring/stripping tool.
A current market trend is to replace traditional copper material coaxial cables with aluminum material coaxial cables to save materials cost and lower the weight per unit length of the coaxial cable. Further, smooth wall outer conductor cables provide inherent materials cost and cable weight advantages compared to corrugated outer conductor coaxial cable configurations.
Aluminum has lower mechanical strength properties including cold work properties (bending) compared to copper. Aluminum is susceptible to creep and may weaken at a single contact point with extreme contact pressure due to bending, pulling and/or twisting.
Smooth wall cable is less flexible compared to corrugated cable; however, users used to working with corrugated coaxial cable may not recognize the lower bend capability of smooth wall cable. Users attempting to apply improper bend radii may overstress a conventional coaxial connector and cable interconnection.
Competition within the coaxial cable and connector industry has focused attention upon improving electrical performance as well as reducing manufacturing, materials and installation costs.
Therefore, it is an object of the invention to provide a method and apparatus that overcomes deficiencies in such prior art.